If the caller of DB_NAME is not the owner of the database and the database is not master or tempdb, the minimum permissions required to see the corresponding row are ALTER ANY DATABASE or VIEW ANY DATABASE server-level permission, or CREATE DATABASE permission in the master database. The database to which the caller is connected can always be viewed in sys.databases.

Important

By default, the public role has the VIEW ANY DATABASE permission, allowing all logins to see database information. To block a login from the ability to detect a database, REVOKE the VIEW ANY DATABASE permission from public, or DENY the VIEW ANY DATABASE permission for individual logins.